Submission #979815

#	Time	Username	Problem	Language	Result	Execution time	Memory
979815		c2zi6	Hexagonal Territory (APIO21_hexagon)	C++14	47 / 100	102 ms	197456 KiB

hexagon

#define _USE_MATH_DEFINES
#include <bits/stdc++.h>
#define ff first
#define ss second
#define pb push_back
#define all(a) (a).begin(), (a).end()
#define replr(i, a, b) for (int i = int(a); i <= int(b); ++i)
#define reprl(i, a, b) for (int i = int(a); i >= int(b); --i)
#define rep(i, n) for (int i = 0; i < int(n); ++i)
#define mkp(a, b) make_pair(a, b)
using namespace std;
typedef long long ll;
typedef long double ld;
typedef pair<int, int> PII;
typedef vector<int> VI;
typedef vector<PII> VPI;
typedef vector<VI> VVI;
typedef vector<VVI> VVVI;
typedef vector<VPI> VVPI;
typedef pair<ll, ll> PLL;
typedef vector<ll> VL;
typedef vector<PLL> VPL;
typedef vector<VL> VVL;
typedef vector<VVL> VVVL;
typedef vector<VPL> VVPL;
template<class T> T setmax(T& a, T b) {if (a < b) return a = b; return a;}
template<class T> T setmin(T& a, T b) {if (a < b) return a; return a = b;}
#include <ext/pb_ds/assoc_container.hpp>
using namespace __gnu_pbds;
template<class T>
using indset = tree<T, null_type, less<T>, rb_tree_tag, tree_order_statistics_node_update>;
#include "hexagon.h"

const ll MOD = 1e9 + 7;

namespace TEST2 {
	ll binpow(ll a, ll b) {
		if (b == 0) return 1;
		if (b & 1) return a*binpow(a, b-1) % MOD;
		ll ret = binpow(a, b/2);
		return ret*ret % MOD;
	}
	ll inv(ll x) {
		return binpow(x, MOD-2);
	}
	ll sum(ll n) {
		return n*(n+1) % MOD * inv(2) % MOD;
	}
	ll sumsq(ll n) {
		return n * (2*n+1) % MOD * (n+1) % MOD * inv(6) % MOD;
	}
	int solve(int n, int A, int B, VI D, VI L) {
		ll x = L[0]+1;
		ll mas1 = sum(x) * A % MOD;
		ll mas2 = (sumsq(x) + MOD-sum(x))%MOD * B % MOD;
		return (mas1 + mas2) % MOD;
	}
}
namespace TEST3 {
	int table[5000][5000];
	int dist[5000][5000];
	VPI harevan(int i, int j) {
		VPI ret;
		ret.pb({i-1, j});
		ret.pb({i, j+1});
			ret.pb({i+1, j+1});
		ret.pb({i+1, j});
		ret.pb({i, j-1});
			ret.pb({i-1, j-1});
		return ret;
	}
	void dfs(int i, int j) {
		table[i][j] = 3;
		for (auto[vi, vj] : harevan(i, j)) if (table[vi][vj] == 2) {
			dfs(vi, vj);
		}
	}
	int solve(int n, int A, int B, VI D, VI L) {
		int ui = 2500, uj = 2500;
		rep(i, n) {
			int dir = D[i]-1;
			rep(j, L[i]) {
				auto[vi, vj] = harevan(ui, uj)[dir];
				table[ui][uj] = 1;
				ui = vi;
				uj = vj;
			}
		}
		int lmi, lmj = 1e9;
		replr(i, 1, 4998) replr(j, 1, 4998) if (table[i][j] == 1) {
			for (auto[vi, vj] : harevan(i, j)) {
				if (table[vi][vj] == 1) continue;
				if (vj < lmj) {
					lmi = vi;
					lmj = vj;
				}
				table[vi][vj] = 2;
			}
		}
		dfs(lmi, lmj);
		replr(i, 1, 4998) replr(j, 1, 4998) if (table[i][j] < 3) table[i][j] = 0;
		replr(i, 0, 4999) replr(j, 0, 4999) dist[i][j] = 2e9;
		queue<PII> q;
		q.push({2500, 2500});
		dist[2500][2500] = 0;
		VI ans{0};
		while (q.size()) {
			auto[ui, uj] = q.front();
			q.pop();
			for (auto[vi, vj] : harevan(ui, uj)) if (table[vi][vj] == 0 && dist[vi][vj] == 2e9) {
				dist[vi][vj] = dist[ui][uj]+1;

				ans.pb(dist[vi][vj]);

				q.push({vi, vj});
			}
		}
		ll ret = 0;
		for (int x : ans) {
			ll cur = (A + 1ll * x * B) % MOD;
			ret += cur;
			ret %= MOD;
		}
		return ret;
	}
}
namespace TEST5 {
	template<class T>
	struct POINT {
		T x, y;
	};
	template<class T>
	POINT<T> perp(POINT<T> a) {
		return {-a.y, a.x};
	}
	template<class T>
	POINT<T> operator+(POINT<T> a, POINT<T> b) {
		return {a.x + b.x, a.y + b.y};
	}
	template<class T>
	POINT<T> operator-(POINT<T> a, POINT<T> b) {
		return {a.x - b.x, a.y - b.y};
	}
	template<class T>
	T operator*(POINT<T> a, POINT<T> b) {
		return a.x*b.x + a.y*b.y;
	}
	template<class T>
	T operator^(POINT<T> a, POINT<T> b) {
		return perp(a) * b;
	}
	template<class T>
	T ccw(POINT<T> a, POINT<T> b, POINT<T> c) {
		return (b-a)^(c-a);
	}
	


	int solve(int n, int AK, int BK, VI D, VI L) {
		ll B = 0;
		for (int x : L) B += x;
		vector<POINT<ll>> polygon;
		polygon.pb({0, 0});
		rep(i, n) {
			auto[x, y] = polygon.back();
			int l = L[i];
			if (D[i] == 1) x -= l;
			else if (D[i] == 2) y += l;
			else if (D[i] == 3) x += l, y += l;
			else if (D[i] == 4) x += l;
			else if (D[i] == 5) y -= l;
			else if (D[i] == 6) x -= l, y -= l;
			polygon.pb({x, y});
		}
		/* for (auto[x, y] : polygon) cout << x << " " << y << endl; */
		ll S = 0;
		rep(i, n) {
			S += ccw(polygon[0], polygon[i], polygon[i+1]);
		}
		S = abs(S);
		ll I = (S-B+2)/2;
		/* cout << "B: " << B << endl; */
		/* cout << "I: " << I << endl; */
		return (I+B)%MOD * AK % MOD;
	}
}

int draw_territory(int n, int A, int B, VI D, VI L) {
	if (n == 3) return TEST2::solve(n, A, B, D, L);
	if (B == 0) return TEST5::solve(n, A, B, D, L);
	return TEST3::solve(n, A, B, D, L);
}

Compilation message (stderr)

hexagon.cpp: In function 'void TEST3::dfs(int, int)':
hexagon.cpp:74:12: warning: structured bindings only available with '-std=c++17' or '-std=gnu++17'
   74 |   for (auto[vi, vj] : harevan(i, j)) if (table[vi][vj] == 2) {
      |            ^
hexagon.cpp: In function 'int TEST3::solve(int, int, int, VI, VI)':
hexagon.cpp:83:9: warning: structured bindings only available with '-std=c++17' or '-std=gnu++17'
   83 |     auto[vi, vj] = harevan(ui, uj)[dir];
      |         ^
hexagon.cpp:91:13: warning: structured bindings only available with '-std=c++17' or '-std=gnu++17'
   91 |    for (auto[vi, vj] : harevan(i, j)) {
      |             ^
hexagon.cpp:108:8: warning: structured bindings only available with '-std=c++17' or '-std=gnu++17'
  108 |    auto[ui, uj] = q.front();
      |        ^
hexagon.cpp:110:13: warning: structured bindings only available with '-std=c++17' or '-std=gnu++17'
  110 |    for (auto[vi, vj] : harevan(ui, uj)) if (table[vi][vj] == 0 && dist[vi][vj] == 2e9) {
      |             ^
hexagon.cpp: In function 'int TEST5::solve(int, int, int, VI, VI)':
hexagon.cpp:165:8: warning: structured bindings only available with '-std=c++17' or '-std=gnu++17'
  165 |    auto[x, y] = polygon.back();
      |        ^
hexagon.cpp: In function 'int TEST3::solve(int, int, int, VI, VI)':
hexagon.cpp:100:6: warning: 'lmi' may be used uninitialized in this function [-Wmaybe-uninitialized]
  100 |   dfs(lmi, lmj);
      |   ~~~^~~~~~~~~~

• Subtask 1: 3 / 3
• Subtask 2: 6 / 6
• Subtask 3: 11 / 11
• Subtask 4: 12 / 12
• Subtask 5: 15 / 15
• Subtask 6: 0 / 19
• Subtask 7: 0 / 18
• Subtask 8: 0 / 16